1. Field of Invention
The present invention relates generally to the field of telecommunications. More particularly, in one exemplary aspect, the present invention is directed to methods and apparatus for reducing data transmission overhead by delaying transmission of data.
2. Description of Related Technology
Most wireless communication systems establish a logical “connection” between the source device and destination device (or network) before transmitting data. Such connectivity enables desirable connection qualities and capabilities, such as inter alia, physical resource management, multiplexed access, Quality of Service (QoS) guarantees, link management, data security, etc. However, connection establishment is a non-trivial process that often involves multiple entities, transactions, and negotiation sequences, and which can require an appreciable amount of time to complete. For example, connection establishment for cellular phone type mobile devices can span from hundreds of milliseconds to several seconds. In many cases, such connection latency is perceptible to the user, and if protracted can lead to significant user frustration.
So-called “idle” states (and other analogous “dormant” state variations) are used throughout the related arts to minimize the network overhead associated with repeatedly bringing up, and tearing down connections. Excessive amounts of connection transitions e.g., bringing up and tearing down connections (also referred to as “churn”) is highly undesirable.
For example, FIG. 1 illustrates one genericized state diagram for prior art connection management between two wireless peers. In the disconnected state 102, a first device does not have a connection to any peer devices. In some systems, the first device can put its modem in a low power, or even an unpowered state. Responsive to a connection request (e.g., initiated by a user, etc.), the first device transitions to a connected state 104; during the connected state, the first device can transmit data to a second device. Once the first device has finished transmitting its data, the first device transitions to an idle state 106 and waits for newly arriving data. During the idle state, the first device sustains some minimal level of communication to keep a connection open e.g., physical resources, etc. (as opposed to the disconnected state 102, which does not sustain any level of communication.) By keeping the wireless signalling channels open, the modem can instantly serve subsequent data communications by returning to the connected state 104; reusing the existing connection reduces connection churn. However, if no subsequent data is available for transfer within the fixed time interval, the first device disconnects and returns to the disconnected state 102. Typical prior art implementations wait in the idle state for a fixed time interval (e.g., between five (5) to twenty (20) seconds).
Network efficiency can be thought of as the resources which are used to transmit data (e.g., the consumed bandwidth, actual transmission time, etc.) divided by the total resources committed by the network (e.g., the bandwidth allocated, total timeslots, etc.) For example, in a time division multiplexing scheme having eight (8) timeslots, one idle device holds one (1) timeslot for the duration of the idle period; if all other timeslots are operating at full capacity, the network efficiency is 87.5% (seven (7) used timeslots divided by eight (8) assigned timeslots).
Consequently, even though an idle connection 106 uses fewer resources than an active connection 104, the idle state still requires bandwidth and processing resources to sustain the idle state connection. Thus, while longer idle periods can reduce the frequency of connection re-establishment (and the associated overhead), excessively long idle periods adversely affect overall network efficiency.
As previously mentioned, connection establishment can span from hundreds of milliseconds to several seconds; idle periods last between five (5) to twenty (20) seconds. Clearly, while idle periods reduce connection churn, the inefficient use of network resources during idle operation is less than optimal. A better solution is required. Ideally, network efficiency can be improved by eliminating inactive network use or reducing non-data signalling (e.g., idle mode operation, control signalling, etc.)